Naphtholic couplers

ABSTRACT

GIVE RISE TO CYAN DYES FOR USE IN COLOR PHOTOGRAPHIC ELEMENTS UPON COLOR DEVELOPMENT.   Naphtholic couplers of the structural formula:

United States Patent [191 Coraluppi et al.

[ NAPHTHOLIC COUPLERS [75] Inventors: Enzo Coraluppi; Elio de Saraca,

both of Carcure; Lorenzo Vittore, Pietra Ligure. ltaly [73] Assignee: Minnesota Mining and Manufacturing Company, St. Paul. Minn.

[22] Filed: Dec. 1. i972 [2|] Appl. No.: 311.317

[44] Published under the Trial Voluntary Protest Program on January 28. 1975 as document n0.

[5 l] Int. Cl. 603C 7/00; 603C 7/04; 603C l/40; 003C 5/30 [58] Field of Search 96/100. 55. 56.1. 56.6. 96/9 [56] References Cited UNITED STATES PATENTS 2.474.293 6/l949 Weissberger et al. 96/55 Nov. 11, 1975 3.706.684 ll/l952 Graham et a] 96/100 3.237.55l l/l966 Barr el al 96/100 3.615.499 lU/l97l Groet 96/566 3.667.956 6/1972 luumu et a]. 96/!00 Prinmrv E.t'umiuerNorman G. Torchin Assislum E.\'umilwrRichurd L. Schilling Arm/vie Agent. or Firm-Alexander. Sell. Steldt 6'; DeLaHunt [57] ABSTRACT Naphtholic couplers of the structural formula:

03 com! (CH s(o give rise to cyan dyes for use in color photographic elements upon color development.

ll Claims. No Drawings NAPHTHOLIC COUPLERS The present invention relates to couplers for color photography. More specifically it relates to naphtholic couplers which are suitable for incorporation either into color emulsions. or into color developing baths. and gives rise to cyan dyes upon color development.

It is known to the art that couplers of the naphtholic type are capable of reacting with the oxidation products of N.N-dialkyl-p-phenylene diamine type developers to form cyan images in silver halide photographic elements. It is greatly desired that such dye images be highly stable to light. heat and moisture.

The naphtholic type couplers. described in US. Pat. No. 2.474.293. give rise upon color development to dyes which exhibit an insufficient stability to heat and moisture.

It is an object of the present invention to provide naphtholic couplers which are capable of reacting with the oxidation product of a primary amine type developer. to form a dye which is highly stable to light. heat and moisture.

Briefly. the present invention relates to color couplers of the following formula:

aqueous solution. the couplers must be made water-soluble. by means of solvating groups of the SO H and COOH type. In the case they must be incorporated into the emulsion by the solvent dispersion technique. the couplers must be soluble in substantially water-immiscible organic solvents. Such a technique which is now preferred is described for instance in US. Pat. Nos. 2.322.027. 2.801.170: 2.801.171; 2.870.012 and 2.991.177. Briefly the solvent dispersion technique involves first dissolving a coupler in a substantially waterimmiscible organic solvent and then dispersing the soprepared solution as extremely fine droplets in a hydrophilic collodial binder. Gelatin is the preferred colloidal binder. but other polymeric colloidal binder materials. known to the art. can also be utilized. Obviously. when the couplers are incorporated into the emulsion by the solvent dispersion technique. the dyes derived therefrom upon color development are also contained (dispersed) in the emulsion. dissolved in the substantially water-immiscible organic solvent.

Development inhibiting groups. which can be intro duced in the para position to the hydroxyl group. are described for instance in the French Pat. No. 1.257.887 and in its addition No. 78.161: in the French Pat. No.

wherein:

R is H or an alkyl radical having l-l 8 carbon atoms; Z is H or a substituent which is expelled during the coupling reaction with an oxidation product of a primary amine developer; in is 0-1; and n is 1-4.

When R of the above described formula is equal to H or to an alkyl group having a low molecular weight. for example having l4 carbon atoms. the couplers of the present invention can be used as bath couplers." When. on the other hand. R is equal to an alkyl with a high molecular weight. for example having 9-18 carbon atoms. the couplers of the present invention can be incorporated into the emulsion in aqueous solution or by the solvent dispersion technique.

Examples of groups which can be expelled during the coupling reaction are Cl. Br. COOH. SO H which affect the reactivity or solubility of the coupler. or a group having a specific activity on the photographic emulsion. like. for instance. a fog inhibitor or a masking group is intended. Hydrogen is also included amongst those groups which are expelled during reaction with an oxidation product of a primary amine developer.

For bath couplers. those couplers which are dissolved in the color developer are intended. They are therefore designed to be alkali-soluble. to diffuse easily into the appropriate layer and to give the desired colors by formation of dyes which do not diffuse under the processing conditions (see: C. E. Kenneth Mees and T. H. James, The Theory of the Photographic Process.

third edition. page 393).

1.224.012 and in its additions Nos. 75.676 and 77.306; and in the US. Pat. No. 3.364.022. Such groups are expelled during the coupling reaction and act therefore as development inhibiting groups.

The masking groups which can be introduced in the para position to the hydroxyl group are suitable for making an integral mask of a colored negative film. as described in US. Pat. No. 2.449.966. ln accordance with such a process. a colored coupler. containing a chromophore group (Z. in our case) in the reaction position with the oxidation product of the p-phenylene diamine. is incorporated in at least one of the emulsion layers of the photographic element.

The chromophore group is split off during color development with the result that the residual radical is transformed into a dye (cyan dye. in our case). absorbing a major portion of light in one of the primary colors (main absorption: in the red region. in our case) and a minor portion in another region of the visible spectrum (secondary absorption: in the green region. n our case). The colored coupler. remaining in the unexposed parts of the layer. does absorb in the above mentioned green portion and does not absorb in the red one. With such a technique an element is obtained. which exhibits a uniform masking coloration." which is substantially independent from the exposure and can be eliminated by filtration during the printing step of the positive photographic element.

The said masking technique is well-known to the man skilled in the art and is carried out in an improved way. employing uncolored couplers in conjunction with color couplers. as described for instance in the US. Pat. Nos. 2.428.054: 2.808.329; 2.860.975; and 2.852.370. Colored couplers having chromophore groups which can be usefully introduced into the cou- 3 plers of the present invention. are for instance the azogroups. like those described in the US. Pat. Nos. 152L908; 2.657.134; 2.706.684: 3.034.892.

It has been experimentally observed that the most useful couplers for an effective masking are those corresponding to the following formulae: .15/17 wherein:

R is an alkvl having 9-l 8 carbon atoms: :1 is 1-4; X

is CO-alk \l: Y is H or halogen; m is t) l.

H u l CONH (CH 4 wherein:

P is a p-phenvlene diamine residue: m is 0-]: n is I4: and R is H or an alkvl. having 1-18 carbon atoms.

According to the present invention. the above-mentioned d ves. which give rise to a photographic image in photographic silver halide elements. are particularly stable to light. heat and moisture. After exposure. such elements are developed with p-phen vlene diamine tvpe developers Brieflv the present invention relates to silver halide photographic emulsions containing anti-diffusing couplers of the above-described formula. dissolved in a substantially water-immiscible organic solvent. It also relates to an exposed and developed silver halide photographic element. containing dves of the abovedescribed formula. More specificall it relates to an exposed and developed silver halide clement containing dispersed d ves of the above-described formula. dis solved in a substantiall water-immiscible organic solvent. It further relates to p-phenvlene diamine color developing baths containing diffusing bath couplers 0f the abovc-described formula.

The meaning of Z in the formula that describes the bath couplers above must be obviousl interpreted in view of what is knovvn to those skilled in the art. Z is not for instance a masking group because colored COU- plers are embodied into the emulsion and not into the color developing bath. in accordance with the masking technique of colored films described before. As previously specified. bath-couplers must easilv diffuse in the proper laver. It means that Z cannot be a ballasting group. acting as an anti-diffusing group in the molecule. Whatever Z ma be. in this case it must not hinder the diffusion of the molecule. that is to sav it may be either a development inhibiting group of the above-mew tioned type or a group of the Cl. Br. COOH. and SO -;H t vpe.

Couplers of the present invention are for instance the following ones:

00 NH (CH2)2- s Q co NH (CH2)3- s Q 0H co -NH (ox n s Q co NH mu s @011 CO CH \max 505 m u in ethanol Br x max 506 m u in ethanol The following examples will help to further describe The following couplers are similar couplers of the prior art (see: US. Pat. No. 2.474.293) which have the practice of the present invention.

been compared with those of the present invention:

T co NH (011 0 C H co N'H wa o C9H19 c1 c) on i co NH (CH2)3 n) on o NH (011 M 0 1-1 co NH (011 o cn EXAMPLE 1 B-phenyl-thio-ethy l-amine 55.09 g. of thio-phenol (0.5 moles) and 250 ml. of absolute ethyl alcohol were introduced into a multineck flask provided with a stirrer. a condenser and a dropping funnel. 23 g. of Na (l mol) were added thereto and. after the reaction. an alcohol solution of I014 gv of Z-hromoethylamine bromo-hydrate (0.5 moles) was dropped into the flask. After boiling and removal of the alcohol under vacuum. the residue was poured into H O. The oil. thus obtained. was extracted with ethyl ether; after evaporation otthe ether. the residue was purified by distillation. thus obtaining 37 g. of the product (hp 1 l6l l7/2mm Hg). AnalysiszNH "/5 98.14. l-oxy -N-[ [34 phenyI-thio l-ethy l l-l-naphtamide 30.6 g. of B-phenyl-thio-ethyl-amine (02 moles) and 52.8 g. of phenyl l-oxy-Z-naphtoate (0.] moles) were introduced into a Claysen flask. The mixture was melted and then the phenol. thus formed in the reaction. purified by distillation. The residue was crystallized from ethyl alcohol. thus obtaining 53.6 g. of the product (m.p. 9l92C).

Analysis OH 1 N50 Calculated l-ound S: L'Jl L77 EXAMPLE I 'y-phen vl-thio-propy l-am ine It was prepared like ,B-phenyl-thio-ethy l-amine of Example l. In this case. 3-bromo-propyl-amine bromohydrate was used. thus obtaining 25.1 g. (hp. lll l' /1.2 mm. Hg).

Analysis; NH 1 48.61

Calculated Found l-oxy-N-l 'y-t phenyl-thio l-propyl l-l-naphtamide 36.7 g. of the above-mentioned compound were pre pared like the compound of Example I (m.p. 9596C Calculated Found t 7 I .IU 703!) H! 5.68 569 X: 4. l 4.19 S" 9.50 9 50 Analysis OH 7( 9813.

EXAMPLE 3 Calculated Found Nr 7.90 7 66 S: l 8 ()8 18. l 4

6-phenyl-thio-butylamine 1.500 ml. of ethyl ether anhydrous and 28.5 g. of Li A] H (0.75 moles) were introduced into a multi-neck flask. provided with a stirrer. a condenser and a dropping funnel. An ethereal solution of 88.6 g. of 'y-phenylthio-butyrronitrile (0.5 moles) was prepared and then slowly added into the flask. After the reaction. the Lithium and Aluminum hydride. which had not reacted. was destroyed with caution by addition of H 0 and NaOH. The suspension. thus obtained. was filtered and the residue repeatedly washed with ether: the ethereal solutions were washed until the washings were neutral and dried on sodium sulphate anhydrous. After evaporation of ether. the residue was purified by distillation under vacuum. thus obtaining 69.8 g. of the product {b.p. l52l54C/0.7 mm. Hg.). AnalysiszNHf/r 99. l-oxyN-l 5-( phenyl-thio )-butyl l-lnaphtamide With a similar process of Example I. a product was obtained. having a melting point ranging from 99 to 101C.

Analysis: ()H'r 99.57

Calculated Found 5': 9.] l 9.07 NH 398 3.89

EXAMPLE 4 y-4-methyl-phenyl-thio-butyrronitrile It was prepared like y-phenyl-thio-butyrronitrile (see Example 3). thus obtaining a product. having a lap. ranging from 148 to 155C/l mm. Hg.

Analysis: Calculated Found 2 6917 68.77 HQ 6 6.84 NG 7.32 7.12 S! l6.76 I680 Analysis. OHQ l0(l.-l

Calculated Found t 712*) 72.40 H' 6.34 6.36 N; 3.83 3 86 S'( 8.77 8.80

EXAMPLE 4-tolyl-sulpho-acetonitrile 50 g. of sodium p-toluene-sulphonate tetrahydrate (02 moles). 200 m1. of propanol and g. of chloroacetonitrile (0.2 moles) were introduced into a flask. provided with a condenser and then refluxed on a water-bath. After the reaction, the compound was filtered and then cooled at 0C. The precipitate. thus formed. was filtered and dried. thus obtaining 29.2 g. of the product. which were suspended in dioxane. The suspension was heated lightly and NaOH added thereto until a complete solution was obtained. The solution was then poured into H 0 and acidified with HCl. thus obtaining a precipitate. which was separated and dried. In such a way. 20.5 g. of the product were obtained (mp. 146-148C). The material was crystallized from ethanol. thus obtaining 18.4 g. of the product. melting at 148-150C. B-4-tolyl-sulpho-ethylamine A suspension of 18.4 g. of 4-toly1-sulpho-acetonitrile in ethyl-alcohol and 3 g. of Nickel-Raney were introduced into an autoclave. Hydrogen was then introduced thereinto until a pressure of atm. was reached and the temperature increased up to 100C. After the reaction. the autoclave content was removed. filtered to remove the Ni-Raney and the solvent distilled under vacuum. After distillation of the oily residue. 6.5 g. of the product were obtained (b.p. l40-155C /0.4 mm. l-oxy-N-[ B-( 4-tolyl-sulpho )ethyl l-2-naphtamidc The product was obtained like the one of Example 1. M.p. 166l68C.

Analysis: OH'J 9854-8 Calculated Found Ni? 3.79 3.59 S'/ 8.67 8.421

EXAMPLE 6 B-4-nonyl-phenyl-thio-ethylamine The compound was prepared like B-phenyl-thioethylamine of Example 1. using however a p-nonylthio-phenol FLUKA, thus obtaining 57.4 of the product (b.p. 2122l7C/18 mm. Hg). Analysis: NH 7c 95.5. l-oxy-N-l B- 4-nonyl-phenyl-thio )-ethyl -2-naphtamide It was obtained like the product of Example 1. After crystallization from acetonitrile. 62.4 g. of the product were obtained (m.p. 39-4lC).

Analysis: OH'.) 96.5

Calculated Found N/:' 3.11 2.93 5% 7.13 7.18

EXAMPLE 7 case the product was crystallized from ethanol. M.p. 73C.

y-4-nony1-phenyl-thio-butyrronitrile See Example 3 for the preparation of 'y-phenyl-thiobutyrronitrile. in this case p-nonyl-thio-phenol FLUKA was used and 230 g. of the product were obtained. B.p. 202-2l0C/2.7 mm. Hg.

Analysis: Calculated Found 6-4-nonyl-phenyl-thio-butylamine See Example 3 for the preparation of 5-phenyl-thiobutylamine. 21.3 g. of the product were obtained. B.p. l202C/1.8 mm. Hg.

Anal sis: '.\'H- 'i 99.8

Calculated Found ("7 74.33 73.7 H. ltLNl lnnu 4.55 4.55 S; 111.4: 111.1

Analysis: OH" 100.7

Calculated Found N; 2.93 2.85 S) (1.71 6.45

EXAMPLE 9 6-4-nonyl-pheny1-thio-butylamine 78.5 g. of 5-4-nonyl-phenyl-thio-butyl-amine (0.254 moles) see Example 8. 26g. of acetic anhydride (0.254 moles) and 20.9 g. of sodium acetate anhydrous (0.254 moles) were introduced into a multi-neck flask provided with a stirrer and a condenser. After boiling under stirring. the mixture. thus obtained. was poured into H 0 and ice. The water was decanted and the oily mass dissolved in ethyl ether. The solution was evaporated and the oily residue purified by distillation under vacuum. thus obtaining 70.3 g. of the product. boiling at 280C/5.2 mm. Hg.

Analysis: Calculated Found ("i 72.14 71.88 HQ 10.09 101). N52 4.01] 4.311 SQ 9.1 7 9.37

6-4-nonyl-phenyl-sulpho-butylamine 67.5 g. of 5-4-n0nyl-phenyl-thio-butylaeetaminc (0.193 moles) and glacial acetic acid were introduced into a multi-neck flask provided with a stirrer. a condenser and a dropping funnel. The mixture was refluxed and l35ml. of H- .O at 36% were dropped thereinto. After the oxidation reaction. the acetic acid was removed by distillation under vacuum. A hydroalcoholic solution of KOH5N was added to the oily residue and then refluxed until it was completely hydrolyzed. The solution was then poured into water and the oily product. having been separated. was extracted with ethyl ether. The ethyl ether was then removed by distillation and the oily residue (44 g.) used as it was. l-oxy 5-( 4-nony l-phenyLsulpho )-but I ]-Z-naphta-' mide See Example 1 for the preparation of the above-mentioned compound. The product thus obtained. was recrystallized from methanol. M.p. l()4-lU5C.

Analysis: ()H'l llNl.

Calculated Found C, 7am 7o}? H'v 7.7l 7.64 NH 2.74 2.70

EXAMPLE ll) l-oxy -4-chloro-I\'-[ 5-( 4-nonyl-phenyl-thio )but I ]Z- naphtamide The condensation between phcnyl l-oxy-4-chloro-Z- naphtoate and 8-4-nonyl-phenyl-thio-butylamine was carried out as in Example I The condensation product was crystallized from methanol. M.p. 43l5C.

'y-4-decyl-phenyl-thio-butyrronitrile It was prepared like y-4-nonyl-phcnyl-thio-butyrronitrile (Example 8). using p-decyl-thiophenol [prepared as described in Zh. Obsheh. Khem. 34 (3) 993-995 1964)]. B.p. 227236C/l mm. Hg.

Anal sis: Calculated Found N: 4.4 4.1 l S; 9.74 HIM) Analysis: ()H'( 98.34

Calculated Found CH 75.71 75.71) H! 5.4M X 5 .\'v N4 1.72s S" 6.53 o is l-oxy-N-I 8-( 4-decyl-phenyl-thio )-eth l ]Z-naphtamide It was prepared like the product of Example 6. In this case. p-decyl-thio-phenol was used as a starting procluct.

Analysis:OH.1 99.0

EXAMPLE [3 l-oxy-4-( l-phenyl-5-tetrazolil-thio )-l\'-| 8-( 4-nonylphcny l-thio )-but I l-I-naphtamide.

42.53 g. of bis-( l-phenyl-5-tetrazolil )-disulphide ((1.!2 moles) prepared as described in Berichte 28. 8| and carbon tetrachloride were introduced into a flask provided with a bubbler and condenser. chlorine was then bubbled into the suspension until a complete solution was reached. The solvent was evaporated and the residual orange oil was dissolved in carbon tetrachloride. The solution. thus obtained. was added to a carbon tetrachloride solution of I 14.6 g. of l-oxy-N-[5- (4-nonyl-phenyl-thio t-butyl I-Z-naphtamide (U24 moles). which was prepared in another flask provided with a condenser and a stirrer. After boiling the solvent was removed and the solid residue crystallized from methyl alcohol and further from isopropylic alcohol. Mp. l12l l5C l-oxy-4-phenyl-thio-N- B-( 4-decyl-phenyl-thio ethyl I-Z-n aphtamide A solution of 69.5 g. of l-oxy-N-[B(4-decyl-phenylthio)-ethyll-lnaphtamide (0. l5 moles) in 500 ml. of carbon tetrachloride. being dried on C aC l was introduced into a multi-neck flask provided with a stirrer. a condenser and a dropping funnel. Another solution of Z [.7 g. of sulphinil chloride (0. l5 moles) in 150 ml. of carbon tetrachloride was dropped thereinto at room temperature (25C.). The mixture was then refluxed for 4 hours. The solvent was removed by distillation under water pump vacuum; the oily residue was crystallized from acetonitrile; and finally an oily product was separated by cooling the mixture. Such a product. after the solvent was decanted. was dried in a stove. thus obtaining 67.5 g. of an oily. thick and very dark product. Yield 78.6%

Analysis: Calculated Found EXAMPLE 15 of H were placed into a beaker provided with a stirrer and a thermometer. The solution. thus obtained, was cooled at a temperature ranging from 0 to C and a solution of 3.7 g. of sodium nitrite (0.0535 moles) EXAMPLE l9 l-oxy-4-( 2-acetyI-S-bromo-phenylazo )-N-[ 54 4-decylphenyl-thio J-butyl ]-2-naphtamide It was prepared like the product of Example 18. using dissolved in 23 ml. of water added thereto. I I 5 the Compound of Emmplta 1 L Mp [06040900 After removal of the nitrous acid surplus by addition y 505 i cthanoy of sulphammic acid. the solution was dropped under stirring into a pyridine solution of 23.85 g. of l-oxy-N- Analysis: on. nu .ll [644-nonyl-phenyl-thio) -but \'l]-2-naphtamidc (0.05 v 'L l fi'g moles). previously prepared in a beaker keeping the ID temperature at 0C. After standing and pouring the so- EXAMPLE 7U lution into H O. the precipitate was filtered. washed and dried. thus obtaining 24 g. of the product. M.p. 9 Pl Y 'l L "t henyl-thlol-butyl -na htannde 1.7 l. l C. P y P m 5 5 in cthy] alcohol, It was prepared like the product ot Example l 8. using the compound of Example 8. M.p. l l4-l 16 C b- 99118 )tmax 506 in ethyl alcohol.

Calculated Found c'. v3.1a 73.4: '1 7.27 733 Analysis: ()H" 99.90 N! 6.73 6.69 20 Calculated l-ound st? 5.14 5.13 x ins 5.89

EXAMPLE 16 The couplers of the present invention may be used in l Oxy 4 (LCarbobutylox). phenyl uzo) N [74 con tluiictyon \\'l;lll mzillnyt' typeshot s llyer halal; enliulslnyna; phenyl-thlo)-butyl]-2-naphtam1de WE? f l j g 0 .T P -l; 5; .2 It was prepared like the product of Exumpk: 15 using instance 11n si \cr rontlu. e. si \clrt. on orsi er] alhowever. butyl -2-ammo benzoate instead of 2-ammoi ,m g 9 i ii l 1? Cemphem 1111 3.33; lift-1392 21133321 2.? 211313561 5.; Amax=496inethlalcohol l those emulsions which are described In 05. Pat. lNos. 7 9 4? and 2 698 794 Such couplers can still be Analysis: ()H'i NH. T I

calculated Fmmd used in those emulsions capable oi lormmg an image on "i g; 7 l the surface or in the interior of the silver halide grains. .1; 1;... If: such as those described in us. Pat. No. 2.592.:5u.

As It is known to the man skilled in the art. the above- EXAMPLE l7 mentioned emulsions can be chemically sensitized eil'oxy-4-( 3-carboethoxy-2-naphtylazo )-N-[ 5-( 4-nonylphenyl-thio }-butyl l-2-naphtamide It was prepared like the product of Example 15. using 4 however. ethyl 2-amino-3naphtoate. instead of 2 amino-acetophenon. M.p. l44-147C.

Analysis:OH% 98.85

)tmax 510 in ethyl alcohol.

Calculated Found C5: 73 .36 7355 HQ 7.0l 7.06 N? 6.00 6,02

EXAMPLE l8 Calculated Found C% 64.52 64.8. It 6.14 6. l 3 Br'ri 11.60 H.51 N92 6. l0 6. l 1 SC; 4.66 4.65

ther by addition of sulphur compounds. as described for instance in US. Pat. Nos. l.574.944'. l.623.469 and 2.410.689. and/or by addition of noble metal salts. such as rhutenium. rhodium. iridium. platinum and palladium; or by addition of Au salts. as described in U.S. Pat. No. 2.399.083. They can be stabilized with Au salts. as described in U.S. Pat. Nos. 2.597.856 and 2.597.915. The above-mentioned emulsions can be optically sensitized with cyanine and merocyaninc dyes.

like those described in U.S. Pat. Nos. l.846.30l'. l.846.302'. 1.942.854; 1.990.507: 2.066.967. 2.] l2.l401 2.107.379; 2.l65.338; 2.493.747: 2.493.748; 2.503.776; 2.519.001; 2.666.761

2.734.900; 2.739.149; 2.739.964; and in British Pat. Nos. 450.958 and 466.246.

The emulsions can contain organic stabilizers and anti-foggants of the cylic amine type. iminoazoles. such as mercaptobenzimidazole: triazoles. such as those described in U.S. Pat. No. 2,444,608; azaindenes, such as those described in U.S. Pat. Nos. 2.444.605, 2.444.606; 2.444.609; 2.450.397: 2.713.54 l; 2.7l6.062: 2.735.769; 2.743.l8l'. 2.756.147: 2.772.164 and E. J. Birr in Z. Wiss. Phot. 472 (I952); tetrazoles. such as 1-phenyl-5'mercapto-tetrazole. thiazoles and benzothiazoles. such as l-methylbenzothiazole and benzothiazole quaternary salts. as described in U.S. Pat. No. 2.131.038; mercaptobenzothiazoles. such as l-methylmercapto-benzothiazole; oxazoles; thiosemicarbazides; pyrimidines; iodonium derivatives. benzensulphyn acids; inorganic stabilizers of the zinc and cadmium salt type, such as those described in U.S. Pat. No.

The emulsions can further contain any suitable plasticizer. known to the man skilled in the art. such as glyc erin.

The emulsion may be hardened with any suitable hardener for gelatin. known to the man skilled in the art. such as aldehydes of the formaldehyde. glyoxale. succinic. glutaric and resorcylie aldehyde ty pe'. and halogen substituted aliphatic acids. such as muco chloric and mucobromic acids. as described in US. Pat. No. 2.080.019: or mixture thereof. as described in US. Pat. No. 2.591.542.

The emulsions may have been supplied with a coating aid. known to the man skilled in the art. such as saponin. Any suitable base type. known to the man skilled in the art. can be used. such as cellulose triacetate. polyester. paper. polytenated paper. In the preparation of the silver halide dispersions. employed for preparing silver halide emulsions. there may be employed as the dispersing agent for the silver halide in its preparation. gelatin or another water permeable means of the colloidal albumin type. a cellulose derivative. or a synthetic resin of the polyvinyl type. Such material types are described for instanace in US. Pat. Nos. 2.286.215: 2.328.808: 2.322.085: 2.527.872: 2.541.474; 2.563.791;2.768154111408331: 2.852.382.

If desired. a mixture of two or more of these colloids may be employed for dispersing the silver halide in its preparation.

The developing baths to be used in conjunction with the couplers of the present invention are well-known to the man skilled in the art. They contain a developer of the p-phenylene diamine type. a development re strainer of the potassium bromide type. an antioxidant. such as sodium sulphite and an alkaline agent of the alkali hydrate or carbonate type. They may further contain both an antifoggant of the benzimidazole type and derivatives. of the benzothiazole type and derivatives. of the triazole and tetrazole type and derivatives. such as mercapto-derivatives: and an anticalcium substance of the alkaline phosphate and alkylenediaminopolyacetic acid type. such as for instance EDTA. Compounds. known to the man skilled in the art. of the pphenylcne diamine type are those described for in stance in US. Pat. Nos. 2.193.015: 2.656.273. 2.875.049 and in C. E. Kenneth Mees and T. H. James. The Theory of the Photographic Process." third edition. table 13.4. pages 294-295.

Suitable developers. which can be employed to develop photographic elements. containing the couplers j of the present invention. are the sulphites. the hydrochlorides and the sulphates of:

a. N.N-diethyl-p-phenylene diamine b. N-ethyl.N-B-methansulphonamido-ethyl-3-methyl-4-aminoaniline c. N-ethyl.N-hydroxyethyl-2-methyl-p-phenylene diamine d. N-ethyl.N-hydroxyethyl-p-pheny'lene diamine e. N.N-diethyl-2-methyl-p-phenylene diamine.

EXAMPLE 21 Couplers 6. 7. 8. 9 and 10 of the present invention and those A. B. C and D. outside the present invention. were tested in the following way:

2 g. of a coupler were dissolved in 6 ml. of dibutylphtalate and 12 ml. of ethyl acetate. The solution. thus obtained. was emulsified with 40 ml. of a 4% gelatin solution. in accordance with the prior art. The emulsion was then diluted with water up to 100 ml. and a fraction thereof. containing 0.002 moles of the coupler. was mixed with 200 ml. of a 77( gelatin bromo-chloride emulsion. The resulting emulsion was further coated on a polyester base.

The emulsion specimens. each containing a different coupler. were then exposed to a red light through a decreasing grey step wedge and then developed in a developing bath. corresponding to the following formula:

sodium he\aniela ihosphate 2 g.

sodium sulphite (anhydrous) 4 g.

N.Ndiethyl-2-methyl-p-pheny lene diamine hydrochloride 3 sodium carbonate nionohydrate 20 potassium bromide water to make 1.000 ml.

TABLE 1 Couplers AD'r (i 3.4 7 8.4 8 5 9 12 I0 4 A l8 l5 16 C 17 D 24.

Densities were then read at a conventional densitometer.

EXAMPLE 22 Couplers 3 and 4 of the present invention were compared with couplers E and F. known to the prior art. in the following way:

A specimen of an emulsified photographic element. containing silver halide. was exposed to the light and then developed in a color developing bath containing:

sodium sulphite anhydrous 0.5 g. sodium carbonate l0 g. .\-eth l.\ J3-methansulphonaniidoethy1-3- methy l-4-amino-aniline l g. coupler dissohetl in 10 ml. of ethanol 2 g.

ater to make 1.000 ml.

The specimen was then washed. bleached. washed. fixed. washed again and dried. thus obtaining a cyan image by dye formation.

The specimens. containing the four couplers (3. 4. E. F) were incubated for 24 hours at 90C and 7592 relative humidity.

Table 2 shows the optical density decrease (AD):

Table 2 Couplers AD":

1 7 -l 4.5 E 12.5 F l0.t-

EXAMPLE 23 A colored multi-layer film has been obtained by using a negative type silver halide emulsion in accordance with the following steps:

1. The dibutylphtalate solution of Example 12 was dispersed in gelatin.

2. The dibutylphtalate solution of Example 18 was dispersed in gelatin.

3. Both dispersions were added to a negative silver halide emulsion which had been sensitized to the red.

4. The emulsion of step 3. thus modified. was coated on a transparent base.

5. A gelatin layer was coated over the sensitive emulsion layer.

6. A dibutylphtalate solution of l-phenyl-3-[4-(4- dodecylanilinosulpho )-phenyl-ureido l-5-pyrazolone persed in gelatin.

7. A dibutylphtalate solution of l-phenyl-3-[4-(4- dodecylanilino-sulpho )-phenyl-ureido ]-4-( 4- was dismethoxy-phenylazm-i-pyrazolone was dispersed in gelatin.

8. Both dispersions (6 and 7) were added to a negative silver halide emulsion. being sensitized to the green.

9. The emulsion of step 8. thus modified. was coated as described in steps 4 and 5.

10. A colloidal silver layer. acting as a filter for the blue radiations was coated thereon (step 9).

l l. A dibutylphtalate solution of a-(Z-stearoxy-benzoil)-2-Cl-5-sulpho-phenyl-acetanilide was dispersed in gelatin and further added to a negative silver halide emulsion, which had not been optically sensitized.

12. The emulsion. thus modified. was coated as described at step l0.

13. A gelatin layer was coated on the emulsion of step 12. as a protective layer.

The film. thus obtained. was exposed and further processed in a color developing bath. containing N- ethyl.N-B-methansulphonamidoethyl-3-methyl--laminoaniline. then washed. bleached with potassium ferrocyanide. rewashed. fixed in a hyposulphite bath and finally washed.

A three color negative image was formed. which exhibited a color correction. being stable to light and moist heat.

In the use of the couplers of this invention. the only required function of the group Z is to enable the naphtalic coupler to couple with an oxidized primary aro matic amine color developer through the 4-position where Z is located. The Z group in that para position has already been discussed with regard to the wide variety of groups known in the art to be used in that coupling position.

Z may also be the group --SR where R is an aryl group or an etherocyclic group. When the couplers of this invention are incorporated into silver halide emulsion layers (preferably with a structural base support layer). exposed. and developed with a primary LIFO matic amine color developer. such as for example pphenylene diamine. dye products are formed having the general structural formula R comt (cH s(o wherein:

m. n. and R are as above and P is the residue of an oxidized primary amine color developing agent which has coupled with the couplers of the present invention.

The preferred use for the present compounds is as dye forming couplers for photographic emulsions. This includes the use of these couplers as dispersed coupiers. dissolved in a substantially water-immiscible or ganic solvent. This type of photographic element is well known in the art.

What we claim is:

l. A silver halide photographic emulsion containing at least one coupler of the formula:

Z wherein R is hydrogen or an alkyl radical having lll' carbon atoms; Z is hydrogen or a substituent which is expelled during the coupling reaction with an oxidation product of a primary amine developer; m is (l and l: u is l. 2. 3 and 4.

2. The silver halide photographic emulsion ofclaim 1 wherein the at least one coupler is dissolved in a substantially water-immiscible organic solvent.

3. A p-phenylenc diamine color developing bath containing at least one coupler of the formulai ,COHN- (Cl-l -S O wherein R is hydrogen or an alkyl radical having l-lb' carbon atoms; Z is hydrogen or a substituent which is expelled during the coupling reaction with an oxidation product of a primary amine developer; m is U and l. and n is l. 2. 3 and 4.

4. A silver halide photographic element including a base and at least one emulsion layer which contains at least one dye deriving from a coupler of the formula:

wherein R is hydrogen or an alkyl radical having 1-] 8 carbon atoms: Z is hydrogen or a substituent which is expelled during the coupling reaction with an oxidation product of a primary amine developer: m is U and l; and n is l. 2. 3 and 4 upon color development with a p-phenylenc diamine color developer.

5. A photographic element including a base and at least one silver halide emulsion layer of claim 1.

6. A photographic element containing the silver halide emulsion layer of claim 1 and wherein the coupler is a dispersed coupler with R being an alkyl radical of 9-18 carbon atoms.

7. A photographic element containing the silver halide emulsion layer of claim 1 wherein Z is a development inhibiting group.

8. The photographic element of claim 7 wherein the development inhibitor group is -SR-' wherein R is an aryl or etherocycle group.

9. The photographic element of claim 5 wherein R is an alkyl group having 1-4 carbon atoms. 11. The photographic element of claim 10 wherein [0. The photographic element of claim 5 wherein Z is is an alkyl group having 9-l 8 carbon atoms an arylazo group.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,918,975

DATED 1 November 11, 1975 INVENTOR(S) Enzo Coraluppi, Elio de Saraca & Lorenzo Vittore it is certified that ermt appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 3, line 6, delete "v. 15/17" and insert R OH eoNH (CH s (o 3 Signed and Sealed this Arrest:

RUTH C. MASON c. MARSHALL mum Anrmng Officer Commissioner uj'larems and Trademarks 

1. A SILVER HALIDE PHOTOGRAPHIC EMULSION CONTAINING AT LEAST ONE COUPLER OF THE FORMULA:
 2. The silver halide photographic emulsiOn of claim 1 wherein the at least one coupler is dissolved in a substantially water-immiscible organic solvent.
 3. A P-HENYLENE DIAMINE COLOR DEVELOPING BATCH CONTAINING AT LEAST ONE COUPLER OF THE FORMULA: 1-(O=),2-((R-PHENYL)-S(O2)M-(CH2)N-NH-CO-),4-Z1,4-DIHYDRONAPHTHALENE WHEREIN R IS HYDROGEN OR AN ALKYL RADICAL HAVING -18 CARBON ATOMS: Z IS HYDROGEN OR A SUBSTITUENT WHICH IS EXPELLED DURING THE COUPLING REACTION WITH AN OXIDATION PRODUCT OF A PRIMARY AMINE DEVELOPER: M IS O AND 1, AND N IS 1,2,3 AND 4
 4. A silver halide photographic element including a base and at least one emulsion layer which contains at least one dye deriving from a coupler of the formula:
 5. A photographic element including a base and at least one silver halide emulsion layer of claim
 1. 6. A photographic element containing the silver halide emulsion layer of claim 1 and wherein the coupler is a dispersed coupler with R being an alkyl radical of 9-18 carbon atoms.
 7. A photographic element containing the silver halide emulsion layer of claim 1 wherein Z is a development inhibiting group.
 8. The photographic element of claim 7 wherein the development inhibitor group is -S-R2 wherein R2 is an aryl or etherocycle group.
 9. The photographic element of claim 5 wherein R is an alkyl group having 1-4 carbon atoms.
 10. The photographic element of claim 5 wherein Z is an arylazo group.
 11. The photographic element of claim 10 wherein R is an alkyl group having 9-18 carbon atoms. 